Geomaterials

Sandberg are UKAS accredited to carry out concrete petrography and SEM analysis in accordance with ASTM C856 and APG-SR2. Concrete petrography is supervised by a Sandberg Partner with more than 20 years of experience in petrographic and SEM techniques...

Sandberg has extensive experience with construction in South-West England where so called mundic concrete has been used in building construction and has assisted both the Department of the Environment and the Royal Institution of Chartered Surveyors in preparing their mundic guidelines.

One of the advantages of the SEM is the ability to examine samples at much higher magnifications than by conventional light microscopy. Magnifications in excess of x100000 are possible. Such high magnifications are essential for the characterisation of soil microstructure, cement hydrate morphology and many other applications...

Sulphate attack in concrete has been known to occur when sulphate solutions, derived either from a constituent in the concrete such as aggregate or from external sources such as groundwater, react with the calcium aluminate hydrates present in the hardened cement to form the hydrated calcium sulfoaluminate known as ettringite which can occupy over twice the volume.